Forget the buckshot and stick with slugs. Buckshot doesn't stop a large angry animal. I have dug plenty of 00 shot out of injured African lions that turned into stock killers; sometimes the pellets are just under the skin. I have never needed it, but when darting lions at night I carry a short barreled 11-87 with a Surefire light and loaded with 3" Brenneke's. However, I have used slugs on zebras and similar sized animals for bait and they drop like a rock. As I recall, the standard weapon for Alaskan biologists in bear country is an 870 loaded with slugs.
